1. Field of the Invention
The present invention relates to a binaphthyl compound and an organic light emitting element using the same.
2. Description of the Related Art
The organic light emitting element is an element having a thin film which contains a fluorescence emitting organic compound or a phosphorescence emitting organic compound sandwiched between an anode and a cathode. Electrons and holes (positive holes) are injected from the respective electrodes to generate excitons of the fluorescence emitting organic compound or the phosphorescence emitting organic compound, and the organic light emitting element emits light when these excitons come back to the ground state.
Recent progress in the organic light emitting element is remarkable, which includes high brightness at a low applied voltage, diversification of the wavelength of the emitted light, high-speed response, and reduction in thickness and weight of the light emitting device. From this, the organic light emitting element suggests possibility to broader use.
However, optical power with further higher brightness or higher conversion efficiency is necessary under the present conditions. In addition, there are still many problems in the aspect of durability such as deterioration with time by long time use and deterioration by atmospheric gas containing oxygen and/or moisture. Furthermore, when application to full color displays is considered, emission of blue, green and red lights with high color purity is needed, but it cannot be said that such problems have been fully solved.
In consideration of these problems, there have been conducted a number of studies on aromatic compounds and condensed polycyclic aromatic compounds usable as light-emitting organic compounds which constitute the emitting light layer and the like. It is hard to say, however, that compounds having fully satisfactory emitting light brightness and durability have been obtained.
In the meantime, Japanese Patent Application Laid-Open No. 2004-018510, Japanese Patent Application Laid-Open No. 2004-043349, Japanese Patent Application Laid-Open No. 2005-019219, Japanese Patent Application Laid-Open No. 2005-222948 (corresponding to US 2005/0175857), WO 2005/123634 pamphlet, Japanese Patent Application Laid-Open No. 2006-151966 (corresponding to US 2006/0093857), WO 2006/104044 pamphlet and WO 2007/046658 pamphlet can be mentioned as those exemplifying specific examples of aromatic compounds and condensed polycyclic aromatic compounds usable as light-emitting organic compounds which constitute the light emitting layer and the like.